A 2 MHz 3-port analog isolation and fanout module
- Brookhaven National Lab., Upton, NY (United States). AGS Dept.
In many accelerator based data acquisition systems, signal isolation is a necessary feature so ground loops are avoided. Here, a 3-port isolated circuit providing 1:3 fanout, buffering and amplification over a multi-megahertz bandwidth is presented. The circuit accepts a single input and drives 3 independently isolated output channels, up to {plus_minus} 10 V into 50 ohms. The input and output isolation is supplied via a dual optocoupler, and the power isolation is achieved with DC/DC converters. In each channel, a voltage feedback amplifier is used in combination with the optocoupler to form a transimpedance configuration with the gain-bandwidth product (GBP) set by a pair of resistors. The feedback amplifier linearizes the optocoupler transfer characteristics using a servo technique and also controls the circuit drift, nonlinearity, and bandwidth. The circuit has demonstrated long-term drift of <{plus_minus} .1% of full scale, and resolution to better than 9 bits. The circuit provides frequency response to true DC with an analog bandwidth variable over a range of <100 kHz to >4 MHz, and a SNR of >55 db in a 1 MHz bandwidth with < 1% THD for a 10 V amplitude sinusoidal input. With few modifications, this design is capable of providing input/output gain and bandwidth in the range of 10--50 MHz.
- Research Organization:
- Brookhaven National Lab. (BNL), Upton, NY (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC02-76CH00016
- OSTI ID:
- 52860
- Report Number(s):
- BNL-61115; CONF-950512-8; ON: DE95010348; TRN: 95:011878
- Resource Relation:
- Conference: 16. Institute of Electrical and Electronic Engineers (IEEE) particle accelerator conference, Dallas, TX (United States), 1-5 May 1995; Other Information: PBD: [1995]
- Country of Publication:
- United States
- Language:
- English
Similar Records
Updated design for a low-noise, wideband transimpedance photodiode amplifier
Development of Ultra-Low Noise, Wide Bandwidth, High Gain Transimpedance Amplifiers for Experimental and Commercial Detection Systems